Chemicals most responsible for the toxicity outside this school

Definition: These 15 chemicals, sometimes called polycyclic aromatic hydrocarbons (PAHs), are the result of incomplete combustion of organic compounds. They are found in coal tar, gasoline and diesel exhaust, and wood smoke, and are used in many industries, including steel. Studies have demonstrated that exposure to coke oven
emissions caused lung and urinary cancers in workers. These chemicals are reasonably anticipated to be a human carcinogen. Source: U.S. Department of Health and Human Services

Definition: Sulfuric acid is used in the production of fertilizers and explosives, in the purification of petroleum; in the pickling of metal; and in lead-acid batteries. Breathing sulfuric acid can result in tooth erosion and respiratory tract irritation. Exposures to large quantities at work can increase the incidence of cancers of the larynx, though such workers are often exposed to other chemicals, too. The International Agency for Research on Cancer says occupatonal exposure to inorganic acid mists can cause cancer, but pure sulfuric acid has not been classified. Source: IARC

Definition: Manganese is used to produce pesticides, batteries and other industrial products. Although trace elements are found in food and are considered essential for good health, overexposure for long periods can cause mental and emotional disturbances and slow and clumsy body movements -- a disease of the brain called manganism. Children are more vulnerable to such exposures than adults. EPA says that it cannot be determined if there is a link between manganese and cancer.

Definition: Nickel, a metal, can be combined with other metals to make coins, jewelry, and stainless steel. People working in nickel refineries or nickel-processing plants have experienced chronic bronchitis, reduced lung function, and lung and sinus cancers. EPA classifies nickel refinery dust and nickel subsulfide as human carcinogens.
Source: EPA, HHS

Definition: Glycol ethers are a group of solvents commonly used in paints,liquid soaps and cosmetics. Exposure to high levels of these chemicals can cause liver and kidney damage. Long-term exposure has been linked to anemia, tremors and damage to the neurological system. EPA has not found evidence that these chemicals are linked to cancer. Source: EPA

Sources: U.S. Environmental Protection Agency, University of Massachusetts at Amherst Political Economy Research Institute

* Chemicals most responsible for the toxicity outside this school may not add up to 100% because only the top chemicals are listed.

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